The fund has already been uncorked and made its first deal, leading a $4 million investment in Indonesia-based co-working startup Ev Hive, a source close to negotiations told TechCrunch.

Tan did not respond to requests for comment.

There isn’t a tonne of detail in the filing — which was first spotted by Deal Street Asia — but it looks like Tan has teamed up with fellow Singaporean Lin-Hong Wong to start the new venture. Wong, who has spent time at Singaporean sovereign fund Temasek and the Singapore Economic Development Board, is listed as a director of Insignia Venture Partners within the filing. Wong currently operates a consulting agency called Wingz Capital, and it is unclear whether he will balance that with his role at the fund.

Aside from having worked in the investment space, both men have also authored books on the subject. Tan wrote two books — one on innovation in China and another on general venture capital — while Wong’s title covers venture capital fund management.

A $25 million fund would likely operate in the seed and Series A space in Southeast Asia, a segment that once was seen as a gap but now is becoming well filled with funds. Some of the VCs playing in the space include Golden Gate Ventures ($50 million), Jungle Ventures ($100 million), Venturra Capital ($150 million), and Monk’s Hill Ventures ($80 million.)

Sequoia is one of the few investment funds that operates in the Series A and Series B spaces in Southeast Asia. Despite that and growing interest in the region from major tech companies, with recent deals from Alibaba, Tencent, SoftBank and Expedia, it doesn’t have a dedicated fund. Instead, its Southeast Asia deals are covered by the Sequoia India fund. The current India fund, the firm’s fourth, is the country’s largest VC fund with a total corpus of over $850 million.

Earlier this summer, Sequoia secured $4 billion in fresh financing, including $2 billion for its growth funds, according to a U.S. filing. The firm decline to provide details on how the capital will be allocated, but a good bet is that a large chunk will be put to work in Asia. Indeed, according to report, $125 million of that fresh allocation was funneled into the current India fund.